Set up user access for GKE Identity Service
This document is for cluster administrators who have already configured clusters for GKE Identity Service following the instructions in Configure clusters for fleet-level GKE Identity Service or Configure clusters for GKE Identity Service with OIDC. It tells you how to set up (and restrict) access to your configured cluster for your organization's developers and other cluster users.
Set up user login access
After you have configured a cluster, you need to generate a login configuration file and distribute it to cluster users. This file lets users log in to the cluster from the command line with your chosen provider, as described in Access clusters with GKE Identity Service.
Generate the login config
(Fleet-level setup only)
Copy the displayed
gcloud command and run it to generate the file.
If you configured the cluster using the CLI, or if you need to generate the file again, run the following
create-login-config command to generate the file:
gcloud anthos create-login-config --kubeconfig=KUBECONFIG
KUBECONFIG is the path to the kubeconfig file for the cluster. If there are multiple contexts in the kubeconfig, the current context is used. You may need to reset the current context to the correct cluster before running the command.
You can see complete reference details for this command, including additional optional parameters, in the Google Cloud CLI reference guide.
The default name for the login config file is
kubectl-anthos-config.yaml, which is the name the Google Cloud CLI expects when using the file to log in. If you want to change this to a non-default name, see the relevant section in Distribute the login config below.
For troubleshooting information related to user access, see Troubleshoot user access issues.
Distribute the login config
The following are some possible approaches to distributing the config file:
Host the file at an accessible URL. Users can specify this location with the
--login-configflag when running
gcloud anthos auth login, allowing the Google Cloud CLI to get the file.
Consider hosting the file on a secure host. See the
--login-config-certflag of the gcloud CLI for more information about using PEM certificates for secure HTTPS access.
Manually provide the file to each user, with information on where to save it on their local machine—the Google Cloud CLI expects to find the file in an OS-specific default location. If the file has a non-default name or location, your users must use the
--login-configflag to specify the config file location when running commands against the cluster. Instructions for users to save the file are in Access clusters with GKE Identity Service.
Use your internal tools to push the authentication configuration file onto each user's machine. The Google Cloud CLI expects to find the file in the following locations, depending on the user OS:
Set up role-based access control (RBAC)
Authentication is often combined with Kubernetes role-based access control (RBAC) to provide more finely grained access control to clusters for authenticated users and service accounts. Whenever possible, it is recommended to create RBAC policies that use group names instead of user identifiers. By linking your RBAC policies explicitly to groups, you can manage user access privileges entirely with your identity provider, so the cluster doesn't need to be updated every time user privileges change. Note that to configure access control based on membership of security groups with OIDC, you must ensure that GKE Identity Service is set up to support getting group membership information from your identity provider.
For example, if you wanted certain authenticated users to have access to the cluster's Pods, create a
ClusterRole that grants access to these resources, as in the following example:
apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRole metadata: name: pod-reader rules: - apiGroups: [""] # The resource type for which access is granted resources: ["pods"] # The permissions granted by the ClusterRole verbs: ["get", "watch", "list"]
You then create a corresponding
ClusterRoleBinding to grant the permissions in the
ClusterRole to the relevant users—in this case, members of the
us-east1-cluster-admins security group and the user with ID
apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRoleBinding metadata: name: read-pods-admins subjects: # Grants anyone in the "us-east1-cluster-admins" group # read access to Pods in any namespace within this cluster. - kind: Group name: gid-us-east1-cluster-admins # Name is case-sensitive apiGroup: rbac.authorization.k8s.io # Grants this specific user read access to Pods in any # namespace within this cluster - kind: User name: uid-u98523-4509823 apiGroup: rbac.authorization.k8s.io roleRef: kind: ClusterRole name: pod-reader apiGroup: rbac.authorization.k8s.io
In the following example, this
ClusterRoleBinding grants permissions in the
ClusterRole to the relevant group with ID
12345678-BBBb-cCCCC-0000-123456789012. Note that this setting is relevant only for Azure AD providers and is available for Google Distributed Cloud Virtual for Bare Metal clusters.
apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRoleBinding metadata: name: pod-reader-binding subjects: # Retrieves group information for the group ID mentioned - kind: Group name: 12345678-BBBb-cCCCC-0000-123456789012 apiGroup: rbac.authorization.k8s.io
Create an RBAC role for Google Cloud console access
Users authenticated using OIDC providers can log in to clusters from the Google Cloud console as well as the command line.
Authenticated users who want to access a cluster's resources in the Google Cloud console
need to have the relevant Kubernetes permissions to do so. If you don't want to grant those users more extensive permissions, such as those of a cluster admin, you can create a custom RBAC role that includes the minimum permissions to view the cluster's nodes, persistent volumes, pods, and storage classes. You can define this set of
permissions by creating a
ClusterRole RBAC resource,
cloud-console-reader, in the cluster.
cloud-console-reader grants its users the
permissions on the cluster's nodes, persistent volumes, pods and storage classes,
which allow them to see details about these resources.
To create the
ClusterRole and apply it to the cluster, run the
cat <<EOF > cloud-console-reader.yaml kind: ClusterRole apiVersion: rbac.authorization.k8s.io/v1 metadata: name: cloud-console-reader rules: - apiGroups: [""] resources: ["nodes", "persistentvolumes", "pods"] verbs: ["get", "list", "watch"] - apiGroups: ["storage.k8s.io"] resources: ["storageclasses"] verbs: ["get", "list", "watch"] EOF kubectl apply -f cloud-console-reader.yaml
You can then grant this
ClusterRole to users when setting up your permission policies, as described in the previous section. Note that users also need IAM permissions to view clusters in the Google Cloud console.